In a manual transmission employing a friction clutch in the drive train between the engine and the transmission, a torsional vibration damper is conventionally inserted in the clutch assembly to neutralize the torsional vibrations emanating from the engine which would otherwise result in undesirable characteristics in the transmission. The torque converter of an automatic vehicle transmission effectively hydraulically dampens the torsional vibrations in the system without a separate damper assembly. However, if a lock-up clutch is inserted in the torque converter to provide a direct drive between the impeller and turbine of the torque converter to reduce slippage and increase efficiency at higher speeds, the hydraulic damping action of the torque converter is obviated, and a mechanical damper is again required in the lock-up clutch.